package com.ustcinfo.study.mr.wzg;

import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.mapreduce.Job;
import org.apache.hadoop.mapreduce.Mapper;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.Reducer;
import org.apache.hadoop.mapreduce.lib.input.FileInputFormat;
import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;

import java.io.IOException;

public class ContentIP {
    private static class MyMapper extends Mapper<Object, Text, Text, IntWritable> {
        private static final IntWritable count = new IntWritable(1);

        @Override
        protected void map(Object key, Text value, Context context) throws IOException, InterruptedException {
//            String line=value.toString();
//            String[] arr=line.split(" ");
//            for(int i=0;i<arr.length;i++){
//                Text word = new Text();
//                word.set(arr[i]);
//
//                try {
//                    context.write(word,count);
//                } catch (InterruptedException e) {
//                    e.printStackTrace();
//                }
//            }

            String line = value.toString();
            String ipStr = line.substring(0, line.indexOf(' ')+1);  //返回第一个空格前的ip
            Text word = new Text();
            word.set(ipStr);
            context.write(word, count);

        }

    }

    private static class MyReducer extends Reducer<Text, IntWritable, Text, IntWritable> {
        @Override
        protected void reduce(Text key, Iterable<IntWritable> values, Context context) throws IOException, InterruptedException {
            int sum = 0;
            for (IntWritable val : values) {
                sum += val.get();
            }
            context.write(key, new IntWritable(sum));
        }
    }

    public static void main(String[] args) throws IOException, ClassNotFoundException, InterruptedException{
        Job job = Job.getInstance();

        job.setJobName("wzg_ip_count");

        job.setJarByClass(ContentIP.class);

        job.setMapperClass(MyMapper.class);

        job.setCombinerClass(MyReducer.class);

        job.setOutputKeyClass(Text.class);

        job.setOutputValueClass(IntWritable.class);

        FileInputFormat.addInputPath(job, new Path(args[0]));
        FileOutputFormat.setOutputPath(job, new Path(args[1]));

        int status = job.waitForCompletion(true) ? 0 : 1;

        System.exit(status);
    }
}
